Flameproofing



Patented July 15, 1952 v v I FI ZAMEPROOFING. v .7 Q: -i Y I i ':Morris5L..Nielsen-and.Howard'.-K; Nason,.Dayton, 2

qohios'assignorsjto pa se. S

No -Dra'wingi This? mventionsrelates to. new: .coxxmositions'v of matter; andthemazrmerofr producingithem.. The invention specifically rel'atesr tozmaterials having; utilityffiameprleofmg' compositions: 'witlr the particular. objective? of reducing". the usual diificulty-inregard to the problem of: after-glow.

' ltri'szxanhbiect: or: the invention tolprovidei a composition; of," matter: which.may=' be applied to: combustible. products;- tot reduce? the. danger of after-glow' which is: knowmto be: a property to. resinous. materials. "Ihe invention likewise relates to a preferred methodifor pro-- duoing these compositions;

In accordance with the terminology which has developed in this field; ffiameproofihg means thetratment of. a material 'so' thatii's resistant-to the propagationof flamef across its surfa ffter the igniting flame has been removed;

is; a properly""fiameproofematerial will not support"- com-bustion" independently of an .ex.'-

terna-l source ofheat; Ii'1': contact an open flame, however; or" at elevated temperatures, flameproofed; organic mat'eri'al" can be" expected tocharanddecolmwse p he teclinicalf term" f-fianie prsbfi gv s used accordingto the definitions and requiremerits set forth in the ASTMYStandards 19 44 Y'earboolt-funlder 'l'fest (DGZG HTY BS HI, T930; anti flalso the Army' Quartermaster: Corp's' 'l'est JQDQdZ;

In some flameproofing treatments, specifically those employing metallic oxides, there is an undesirable secondary reaction commonly known; as aften-glowfiby which. is: meant the. flameless: combustion thatimay. occur in a: treatedmaterial such as a fabrie',. after. the. igniting flame has.- bee'nirefiioydjftm thematerialn This phenom. enon on cellulosic fabrics has also been described as afibatalytic. incandescent. oxidation-;;oi the carbon remaining after the initial catalyticspy rogenic decomposition. of the cellulose." Thus, the metal oxides thatare instrumental in bringingabout the desirable suppression; otthe initial pyrogenic. decomposition. in many: cases arepsi-- marily responsible.- for; the production of anzun. desirable. after-glow or: flamelesscombustion!" In thesproblem of reducing the danger-of. fire the. use of; various. resins, particularly irrthe: caseof. resins twhichdo: not.- contain nitrogen; it isfi obvaious. that, the large proportion carbon; hydrogemandoxygen which: are present-tinv such resins}; renders these materials. particularly? sueceptibl'eto; combustion; Evensuch resinous'lmate rials. as: the phenolic: resin. classof: materials have; beenv found glow excessively afterthey Monsanto. Chemical Coma corporationofDelaware 4 Application December 30,1949, serialmnsezl-zr 1; claims. (01. zen-30.6)

have: been in contact with a; flame; so;'that such a: slow combustiomoraftefiglow may entirely consume the? resinous: material; even where only a portion thereof had actually been'consumed by -fl'amin g clombustiomy Such effects; are part'icirlarly' dangerousr in coating, compositions, or otherfextended'or dispersed surfacee of. .g.large areas. which." mawby this; means: propagate am-fire phenomenon. maypernnttheafireto lie-propagated to. otherportions; off thetcoatingx film .;where': othercombustible materialsmayrcauseifiamingi combusvti'cxrtoagain flak-8113135852. It;is;knowmthat metaloxides, such. as antimony oxide; which. have been. utilized in; some: fiameproofingitreatmentsg suchas: in; combination with: polyvinyl; chloride or chlorinated paraffin, aid imthe; catalytic effieot,

which apears to be the cause. of the after-glow phenomenon. For thisreason a fiameless combustion; may- OGCllK even in a treated; material after? the: igniting; flameihas been removed from. the:said:material";v Y r r. KZEhes: present mention; provides compositions reduce-theaftev-glow in combustible: m aterials'sucm as: resins, particularly the group at, phenol-formaldehyde and' resorcinol-formaldee hydet resi nsaz H The present; invention provides compositions.

whichzma-y'ibe applied. to reduce the after-glow combustiblegmaterials; such. 'as-.;cell-u'losicproductsg including cot-ton and; also; regenerated? cellulose;

The. processot.. the" invention; may; be. carried out to obtainrflameprooied products which avoid the prior-artdifiiculty otaiter glowingq.

It has been. found that. fiameproofing compositions employed in combination; wi-tlryacom:

bustiblex-base material'such' asfla cotton rapes may be made with a, negligible;aftereglow ipee rind it such; combinations include. phenol-ieresi-ns imxcombination: with; the reaction product; of; melamine and-phosphorus; pen-torride. -'lihe= preparation of thislatter material" is? described; in (appending? patent applic'ation-,, Seriale"No;.43-,956, filed: August. 12; 1948,.- andassigned," to; the: same assi'gzreeras:isthepresent case; 2 ,g.

It'a. has been: foundr-that the-phenolic: resins combination withsthe -complex; additiorr productof melamine; and.phosphorus:pentoxidemay also: beemployee? in. conventional? fireproofingrcomi positions; as a: specific ingredient to accomplish the chi ectivefof eliminating: therzdangerz of. after-z glows. I The? compcsitioxrof matter emplomedolirrxthei present: :applicattom as: essentiak. nemeonent' be fused by heating to a temperature of about 400 C. The. complex of melamine and,phsphorus pentoxide so obtained is not a phosphate,

as is shown by X-ray diffraction measurements, which also show that the product is an-amorphous rather than a crystalline material. The -pro-' .or,paste..form. However, it may also be mixed portion of the phenolic material-may be .varied widely, a preferred range being from 3% to 90% by weight of the above complex relative to the I phenolic component.

The reaction product from the heating of melamine and phosphorus pentoxide is a white, 'infusiblemass, which may be ground to anfine powder for use: with phenolicziresins' in :glowproofing applications f v If desired, the dry powder may-be suspended in waterwith the aid of dispersing agents and the suspension-applied to fibrous materials known manner. The melamine-phosphorus pantoxide apparently adheres to" or is adsorbed by the base'material to be treated, thereby reducing the burning tendency of'the combustible base material and also the after-burning effect common to untreated materials.

Illustrative of the combination of the phenolic resins-and the melamine-'Pzos'complex with cellulosic-materials, but not limitative of the scope of the "invention, the following example shows an embodiment thereof Example 1 A sample of the melamine-P205 reaction product-prepared as above'wasground to pass a 325 mesh screen. The dry powder thus obtained was mixed with an'equala'mount of a phenol-formaldehyde resin and was dusted on'a piece'of cotton goods, so that approximately 15% by weight'of the mixture was applied. Upontestingthe sotreated cotton it was found that the flammability of the cotton was greatly reduced and the char did not'exhibit any after glow. As little -as 5%" by weight is effective in inhibiting the after-glow; The degree of subdivision may be variedinaccordance'with the desired add-on or method of application. Generally the compound should be ground to pass a 170 mesh screen 'or finer;

Loose cotton fibers, such as batting," wood or plant fibers, such as bagasse in various forms,"

paper and paper products may 'be similarly treated 'withgood results. The application of the phenolic resin in combination with the melamine- PzOs complex to the base material may be made'b'y adry method'of by applying a slurry of the complex dispersed in a liq-ui The use of the phenolicresin in combination with the melamine-phosphorus pentoxide com plex as a glow-proofing agent in the usual flameproofing and fire-proofingcompositions is contemplated in the present invention. It has been found that the use of this new composition solvesthe prior art "difficulty of glowproofing. It has; for example, been previously suggested that com .pounds' of zinc and borony'such as nine borate may be utilized in combination with antimony oxide for the purpose of preventing after-glow,

but I'have found the present investigation that types such as may be produced by molding, extrusion, casting, stamping and other processes.

The composition of matter employed in the present application may be prepared by the dispersion 'or mixing of the melamine-P205 in the phenoliccondensation product while in the liquid with-the resin while the latter is in the form of powder or granules.

It has been found that when such combinations are subjected to a flame, a chemical reaction occurs, with the result that the flammability characteristic of the otherwise combustible resin is greatly reduced, and that the phosphorus com pound which is initiallyinfusible. and insoluble aids'inextinguishing fire andfurthermore en--'. tirely eliminates. any tendency .to;after-'gloW. Illustrative of the-combinationbf-"the.resinous materials, together with the Ereaotion- .product of melamine and phosphorus pentoxide without, however, being limitative of thescope'ofthe invention, the followingexamples further illustratethe invention. i i s I Example 2 A suspension was. prepared from a heat-. ree active condensationproduct of resorcinol and formaldehyde in the form ofapaste ESuc h.

materials, as well as the phenolic resinsggenereally, as contemplated in the present invention are described inv C. Ellis, Chemistry of Synthetic Resins, pages 371-373 (ReinholdPublishing com-. I

pany (1933),). -O nehundred'parts of the con-- densation product were'mixed with 5 parts of the melamine-phosphorus pentoxide reaction .prod-. uct. The combination was appliedas a coating tometal panels. and dried. These test panels;

melamine and phosphorus pentoxide. The mix-f ture may be molded or shape to give resinous burn and which do not smoldering.

for e into y desired. products which do not permit any after-glow. or

Example! The combination mixture of Example 3 was dispersed on'glass fibers of small diameter and the treated material'formed into a block for-"use as. a: heat-insulating material. This material, when subjected to a flame, did not burn; and

did not exhibit any after-glow. A control sample of phenol-formaldehyde on glass fibers, identical but for the absence ofthe' reaction productfof melamine and phosphorus pentoxide, showed a Prolonged glowing period'afterremoval from 'atest flame. Glass fiberstreated iii-the manner" of the present example;'such asby the use er from 3% :to, 50%, by weight, or the phenolic resin combination with the melamine-phosphorus pentoxide, have also been found to be useful as air filters which do not burn and will not glow after a contact with a flame. Other siliceous materials, particularly in attenuated form, such as.

fibrous silica, mineral Wood, and cellular glass, may also be bonded to give a glowproof product by means of the present combination of a phenolic condensation product, together with a condensation product of melamine-P205 as set forth above.

The proportion of the phosphorus compound in association with the phenolic resin may be varied over a wide range, depending upon the pentoxide condensation products per 100 parts by weight of the final mixture.

This application contains subject matter in common with certain other applications assigned to the same assignee as is the present'application: Serial Nos. 43,955 and 43,956 (now U. S. Patent 2,544,706), filed August 12, 1948, the former relating to a method of glowproofing by the application of the complex composition resulting from the reaction of melamine and phosphorus pentoxide. The latter application relates to the preparation of the complex composition resulting from the reaction of melamine and phosphorus pentoxide.

Having now described certain specific forms of the invention, it is to be understood that the invention is not to be limited to the specific forms of compositions herein described or specifically covered by the claims.

What is claimed and isdesired to be protected by Letters Patent of the United States is:

1. A glowproofing composition comprising the combination of a phenolic resin and the reaction product of 2 to 4 moles of melamine and 1 mole of phosphorus pentoxide heated to a temperature of about 400 C., said reaction product being present to the extent of 3% to 90% by weight in said composition.

2. A glow-proofing composition comprising the combination of a resorcinol-formaldehyde resin and the reaction product of 2 to 4 moles of melamine and 1 mole of phosphorus pentoxide heated to a temperature of about 400 C., which latter reaction product is present to the extent of 3% to by weight in said composition.

3. A glowproofing composition comprisingthe combination of a phenol-formaldehyde resin and the reaction product of 2 to 4 moles of melamine and 1 mole of phosphorus pentoxide heated to a temperature of about 400 C., which latter reaction product is present to the extent of 3% to 90% by weight in said composition.

4. The method of producing a glowproof, noncombustible material which comprises treating said material with a dispersion containing the insoluble, heat-reacton product of 2 to 4 moles of melamine and 1 mole of phosphorus pentoxide heated to a temperature of about 400 0., which said product is associated with a phenolic resin to the extent of 3% to 90% by weight of the said heat-reaction product.

5. An insulating material comprising glass fibers rendered glow-proof by the dispersion thereon of a phenolic resin associated with the insoluble, heat-reaction product of 2 to 4 moles melamine and 1 mole'of phosphorus pentoxide heated to a temperature of about 400 C., said heat-re action product being present to the extent of 3% to 90% by weight in said material.

6. A composition of matter comprising an otherwise glow-susceptible phenolic resin, which resin has been rendered glowproof by the addition thereto of from 3% to 90% by weight of the reaction product of 3 moles of melamine and 1 mole of phosphorus pentoxide heated to a temperature of about 400 C.

7. A phenolic resin having associated therewith the heat-reaction product of 3 moles of melamine and 1 mole of phosphorus pentoxide heated to a temperature of about 400 C.

MORRIS L. NIELSEN. HOWARD K. NASON.

REFERENCES CITED UNITED STATES PATENTS Name Date Pollak Mar. 15, 1949 Number 

1. A GLOWPROOFING COMPOSITION COMPRISING THE COMBINATION OF A PHENOLIC RESIN AND THE REACTION PRODUCT OF 2 TO 4 MOLES OF MELAMINE AND 1 MOLE OF PHOSPHORUS PENTOXIDE HEATED TO A TEMPERATURE OF ABOUT 400* C., SAID REACTION PRODUCT BEING PRESENT TO THE EXTENT OF 3% TO 90% BY WEIGHT IN SAID COMPOSTION. 